A key policy question for the coming decade is how best to structure incentives and regulations to insure that frail older hospitalized patients receive cost effective and coordinated care. Both federal and state policy has transformed long term care with the emergence of post-acute care provided by nursing homes (NH) and other providers. Post-acute care now represents approximately 20% of all Medicare spending. Our first Program Project grant focused on the effect of states' Medicaid policies on the strategic choices that NHs make and how those choices impact patient outcomes. We find that not only do states' policies influence providers' investments which can positively or adversely affect residents' outcome, we've also found that Medicare policies affected Medicaid providers and states' Medicaid policies affected Medicare patients, often in a dysfunctional manner. Indeed, Medicare policy changes directed at acute hospitals trickle down to impact most NHs further highlighting the interconnectedness of long term and post-acute care policy domains. Thus, Medicaid and Medicare policies are intertwined; when Medicare policies change, even if only directed at hospitals, NHs and other PAC providers are affected. Since the Affordable Care Act (ACA) represents the biggest policy change to Medicare and Medicaid in decades, we believe it is imperative to understand its effects on the acute care and pOst-acute care interface. The three projects and cores we propose all focus on the growing role of post-acute care (PAC); each has historical aims as well as aims that examine the impact of the Affordable Care Act (ACA). Project #1 asks whether hospitals with strong relationships with NH partners have lower re-hospitalization rates. Project #2 examines the impact of hospitals' approaches to staffing the attending physician role on frail, hospitalized NH residents experience. Finally, Project #3 examines, for the first time, the use of PAC by Medicare managed care and how patients respond to changing co-pay structures for PAC. RELEVANCE (See instructions): Over the last 4 decades long term care in America has been transformed and is now increasingly serving as post-acute care for Medicare beneficiaries recovering from illness. Since the Affordable Care Act (ACA) is the biggest Medicare policy change in decades, we seek to study the evolution of post acute care and its response to the many ACA provisions affecting the scope of hospitals' responsibility post-discharge.